Drive and screw expansion-bolt.



H. W. PLEISTER.

DRIVE AND SCREW EXPANSION BOLT.

APPLICATION FILED APII. II. I9I3.

1.153,83@ Patented. sept. I4, 1915.

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ATTORNEY HENRY W. PLE'ISTER, 0F WESTFIELD, NEW JERSEY, ASSIGNOR TO HENRY B. NEWHALL.

:DRIVE AND SCREW EXPANSION-BOLT.

Specification of Letters Patent.

Patented sept. i4, i915.

Application Yfiled April 11, 1913. Serial No. 760,389.

. following is a specification, taken in connection with the accompanying drawing, which forms a part of the same.

My invention relates to expansion bolts whereby articles are securedto a wall or other support usually of stone, tile, brick, concrete or any other material.

More particularly my .invention comprises an expansion bolt in which the expanding member is driven into the 'shield by a hammer or similar tool so as to quickly expand the shield and then is given a partial rotation to'prevent the expanding member from working loose in or from the shield. Also the rotation of the vexpanding member preferably, though not necessarily, serves to give the shield its final expansion.

ln the accompanying drawing showing illustrative embodiments of my invention and in which the same reference numerals refer to similar parts in the several figures,-Figure l is a vertical section through a support of any suitable material showing the shield expanded, the screw being shown in sidevelevation; Fig. 2 is a vertical section similar to Fig. l except that the bolt or screw is shown in the position to be hit by a hammer or similar member to'thrust it longitudinally into the shield; Fig. 3'is a transverse vertical section substantially on the line 3, 3 of Fig. l looking in the directions of the arrows; Fig. 4 is a plan view of one portion of the shield looking into its interior; Fig. 5 is an end elevation of the preferred form of shield looking into its tapered bore; and Fig. 6 is a transverse vertical section through a slightly modified formof shield; Fig. 7 is a transverse vertical section through a modified form of shield; Fig. 8 is a transverse vertical Vsection through the form of shield shown in Fig. 7, the parts being rotated with relation to each other.l

Fig. 9 is a transverse vertical section through a further modified form of shield. f Fig.

l0 is a transverse verticall section through the form of shield shown in Fig.

9, the parts of the shield being rotated with .y

relation to each other.

ln the illustrative embodiments of my inp vention shown in the drawings, l is an expansion shield preferably formed of a plurality of parts, two being shown for purposes of illustration. Both the lower portion 2-and the upper portion 3 are preferably provided with an inclined interior surface 4, 4, the two together forming an inclined bore 5 for the reception of the eX- panding member 6. l also preferably provide the sections 2 and 3 withinterrupted vscrew threads 7 and 8, respectively. Preferably, though not necessarily, the two sections 2 and 3 together do not form, in the expanded position, a complete circle there being gaps or intervals 9, 9 between the two sections l2 and 3 when expanded, for a purpose which will be hereinafter more fully pointed out, though it is to be understood that my invention is not to be limited to this particular form of shield. l may however, form the shield sothat there would be no gaps or intervals between its two sections. l have shown, by way of example, two such modifications in Figs. 7 to 10 inelusive. But it is of course to be understood that these are merely illustrative.

@ne portion 23 of the shield 22 may carry two tongues 25, 25 to fit into and coperate with the recesses 26, 26 in the other portion 24 of the shield. The length of the tongues 25 and the depth of the cooperating recesses 26 are so arranged, that a partial rotation of one section 23 or 24 with relation to the other, will not entirely withdraw the tongue 25 located opposite to the point of contact of the sections23 and 24, Fig. 8. For purposes of illustration the tongues 25, 25 are shown integral with 'the section carrying them; but this is simply by way of example.

In some cases may form the shield 27 of two sections 28 and 29, Fig. 9, one of the sections for example 28, carries tongues 30 which fit into the cut out grooves 3l, 3l in the other section 29. The parts are so ar- 'y ruptions 11, 11 .in the expanding member 6.

A; hole 12 is formed in the wall of masonry or other material 13 in any suitable manner and the shield formed for example of the sections 2 Aand 3 is inserted th'erein. The work or article supported 14 is then rbrought up to the face of the support 13, the

' expanding member 6 being passed'through it and so positioned as to cause its grooves V.11, 11 to register initially with the intersame.

screw or expanding member is driven in rupted screw threads 7 and 8 in tlie-memybers 2 and 3, bringing the parts substantially in the position shownfin Fig. 2. By

`one or more blows upon the head 15 of the expanding member 6 it is caused to move longitudinally of the shield elements 2 and 3 so as tov quickly and positivelyv expand the In this first movement, when the with a hammer, the screw threads 10 and 7 and 8 areV not in coperation. If the hammerhas driven the expanding member G in sulliciently thefhead 15 is then given a par- -tial revolution sufficient to Cause its screw -threads 10 to engage with the interrupted screw threadsl 7 yand 8 which will then become locking surfacesand prevent the expanding 'member 6 from working loose from the shield. Myinvention further comprises giving the shield elements 2'and 3, if only two are used,

a quickv and positive, expansion by driving the bolt ,or screw into them by a hammer or other tool, and then completing the expansion'of the shield elements 2.and 3 by rotating the expanding member 6 so as to obtain i ythe powerful leverage of the screw threads 10 coperating with the interrupted screw threads 7 and 8 of the'elements 2 and 3. In this manner the shield is expanded to nearly its maximum expansion by simply driving rin the screw or expanding member 6 with a hammer or similar tool, getting the'coinpleteexpansion by afterward rotating the member'l 6 whichwillcause the shield to assume the positionshown at a somewhat ex aggerated angle in Fig. 1, the work 14 being f lbrought tight and true to the face lof the I support 13 and there permanently held fast,

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the screw threads 10 andV the cooperating screw threads 7 and 8 serving as locking surfaces aswell as expanding elements. I

In my preferred form of bolt anchor I Aform the elementv 2 with one or more proyJeetions 17 vso as to form a rouglieiied exterior surface on that element leaving the 'other element 3, for example, substantially smooth; In this preferred construction the elements 2 and 3 are placed in the aperture 12 so'that the interrupted screw threads 7 `est' and 8 arein the same plane, being preferably as shown 180o apart. The grooves 11, 11 in the expanding member (i are also 180o apart so as to receive the interrupted screw threads 7 and 8 as the expanding member 6 is hammered into the shield elements 2 and 3. To lock the expanding member 6 within the shield 1 and to guard against accidental realinement of the grooves 11, 11 with the interrupted screw threads 7 and 8, which would permit the withdrawal of the expanding member 6 by a longitudinal pull or pressure upon it, I preferably make the initial drive of theexpanding member 6 by a hammer or other tool which causes the roughening member or members 17 to bite into the surface of the support so as to prevent the shield element 2 from having any rotative slip in the aperture 12. The periphery of the other shield element 3 being smooth will permit a slight rotative creep of that elenient by rotating the expanding inenibei 6 until its shoulder 18 contacts with the shoulder 19 of the niember`2 when further rotative slip will be prevented. This movement, however, is sufficient to bring the interrupted screw threads 7 and 8 out of alineinent with the grooves or interruptions in the expand- Aing member and into the position shown in Fig. 3. This will prevent any accidental realinenient of the grooves 11, 11 in the expanding member 6 with the interrupted screw threads 7and 8 of the members 2 and 3 and consequently there will be no danger of the work 14 working loose.

'In Fig. G I have illustrated substantially the same form of expansion bolt except that in place of the smooth shield element 3 I employ a shield element 20 having projections 17 the saine as the other shield element. In this form both shield elements will be caused to bite into the wall of the aperture 12 and neither will have a relative slip as in the preferred form illustrated in Fig. 3.

I-Iaving thus described this invention in connection with the illustrative embodiments thereof to the details of which I do not desire to be limited except as required by the scope of the claims, what is claimed as new and what it is desired to secure by Letters Patent is set forth in the appended claims:

1. |The combination in a bolt anchor of an expansion shield and a longitudinally operating primarily non-rotative expanding Amember adapted to expand the shield bv moving longitudinally of the shield and cooperating locking members on the shield `and on the expanding member adapted to be brought into engagement by a partial rotation of the expandingmember.

2. The combination in a bolt anchor of an expansion shield and a longitudinally operating primarily non-rotative expanding member adapted to expand the shield to substantially its maximum expansion, and cooperating rotative expanding inea-ns on the 1,153,335 v i zal;

expanding member and the shield to give the bolt anchor its final expansion by rotating the expanding member.

3. The combination in a bolt anchor of an expansion shield provided with interrupted screw threads, a screw provided with interrupted screw threads, the screw threads of one member being adapted to initially7 register with the interruptions in the other member to permit the screw to be rst hammered into the shield to expand the shield to substantially its maximum expansion, the final expansion being given by the coperating interrupted screw threads upon the screw and the shield.

4:. The combination in a bolt anchor of an expansion shield formed of a plurality of parts provided with interrupted screw threads, a screw provided with interrupted screw threads, the screw threads upon the shield and upon the screw being adapted to be initially disengaged to permit the screw to be hammered into the shield to give it a quick initial expansion, and then rotated to complete the expansion.

5. The combination in a bolt anchor of an expansion shield formed of a plurality of parts adapted to have relative rotative movement with relation to each other, an interrupted screw thread upon the di'erent parts of the shield and a screw having an interrupted screw thread, the interruptions in the screw initially registering with the interrupted screw threads in the different portions of the shield.

6. The combination in a bolt anchor of an expansion shield formed of a plurality of parts adapted to have relative rotative movement with relation to each other, one of the parts of the shield beingprovided with one or more exterior engaging members to prevent its rotation, an interrupted screw thread upon the dierent parts of the shield and a screw having an interrupted screw thread, the interruptions in the screw initially registering with the interrupted screw threads in the diiierent portions of the shield.

7 The combination in a bolt anchor of an expansion shield formed of a plurality of separate and independent parts, and a longitudinally operating primarily non-rotative expanding member adapted to separate the different parts of the shield by moving the expanding member longitudinally of the separate parts of the shield, and coperating locking members carried by the expanding member and the parts of the shield adapted to be brought into engagement by a partial rotation of the expanding member.

8. The combination in a bolt anchor, of an expansion shield formed of a plurality of separate and independent parts and a longitudinally operating primarily non-rotative expanding member adapted to expand the diierent parts of the shield to substantially their maximum expansion, and coperating rotative expanding means on the expanding member and the diiierent independent parts of the shield to give the bolt anchor its iinal expansion by rotating the expanding member.

HENRY W. PLEISTER. Witnesses ALAN M. JOHNSON,

Rosn MENK.

Copies of this patent may be obtained for ve cents each, by addressing the Commissioner of Patents, Washington, D. C. 

